Gas cutting apparatus



TF. STONEBERG,

Dec. 22, 1942.

GAS CUTTING APPARATUS FiledMay 31, 1941 5 Sheets-Sheet l INVENTOR.

flea 520722 be 7 ATTORNEYS.

5 Sheets- Sheet 3 v INVENTOR.

'F. STONEBERG GAS CUTTING APPARATUS Filed May 31, '1941IIIII'IIIIIIIIIIA V Dec. 22, 1942.

Y SZOMZW/ g ATTORNEYS.

D..c. 22, 1942. F. STONEBERG GAS CUTTING APPARATUS Filed May 31 1941 5Sheets-Sheet 4 Jfxzd BY (ham ATTORNEYS.

Dec. 22, 1942 J F. STONEBERG GAS CUTTING APPARATUS 72.; ATTORNEYS.

VINVENTOR.

fled BY 1 Filed May 51, 1941 I Patented Dec. 22, 1942 UNITED STATESPATENTOFFICE ens comma ArPAnA'rus Fred Stoneberg, Chicago, Ill.,assignor to Ga'so Equipment 00., a corporation of Illinois ApplicationMay 31, 1941, Serial No. 395,954

14 Claims.

This invention relates to gas cutting apparatus andmore particularly tothe type in which the cuttingmechanism is transported by a carriage andthe torch supporting arms are guided by the aid of a tracing ortemplate.

.One of the objects of the invention is the pro vision of a new andimproved gas cutting apparatus having novel means for operating theguide mechanism for controlling the movement of the torch supportingarms. A further object of the invention is the provision of a new andsimplified change speed mechanism for varying the speed of the torchsupporting' carriage.

of comparatively few moving parts.

'- Other and further objects and advantages of the invention'will appearfrom the following description, taken in connection with theaccompanying drawings, in which- Fig. lis a top plan view of theapparatus with parts in section and parts omitted for the sake ofclearness;

Fig. 2 is a plan-view of the tracing member;

Fig. 3 is a side elevation of the apparatus;

Fig. 4 is an end elevation thereof Fig. 5 is a side elevation of theapparatus showchart or ing a modified form of tracer head;

Fig, 6 is a section on theline 6-6 of Fig. l; Fig. 7 is a sectionon theline 1-1 of Fig. 6; Fig. 8 is a section on the line 8-8 of Fig. 6; Fig.9 is a section on the line 9-9 of Fig. 6; Fig. 10 is a section on theline Ill-I0 of Fig. 1; Fig. 11 is a section onthe line l|-.|l of Fig.1;Fig. 12 is a section on the line. l2- -l2 of Fig. 10; Fig. 13 is asection on the line l3-l3 of Fig. 5; Fig. 14' is a front elevation'of amodified form of the tractor element, with parts in section;

Fig. 15 is an elevation of-the apparatus showing an attachment forcutting disks;

Fig. 16 is a perspective view of the attachment; v

Fig. 1'? shows a top plan view of a. modified form of the torchsupporting mechanism with parts in section and parts omitted for thesake of cleamess; and v Fig. 18 is a section on the line 18-18 of Fig.17. Referrng now to the drawings, the reference character l0 designatesa gas cutting apparatus which comprises a carriage ll having a bodyportion I2 which may be rectangular in form and an inverted U in crosssection. This carriage, as shown, has a substantially flat top wall 13,Fig. 1

and depending side and end walls It and I5,

respectively, Figs. 3 and 4. The body portion I2 -hasdepending axialsupporting members i5, Fig.

4, adjacent to the corners and these supports are provided with stubaxles H on which are rotatably mounted flanged wheels that are adaptedto engage the tracks I9 and 2! which guide the carriage in itslongitudinal movement. The carriage is adapted to have mounted thereonthe torch supporting mechanism 22 which extends across the carriagebeyond the sides thereof. This mechanism comprises a torch supportingbar 23 on which is mounted a combined gear box and motor'casing 24, asshown more clearly in Figs. 1 and 6 of the drawings.

Suitable means are provided for supporting the 1 bar 23 on the carriagel0 so that the bar may move endwise and be maintained in a positionnormal to the longitudinal axis of the carriage. Any suitable mechanismmay be employed for this purpose. In the form of the device selected toillustrate one embodiment of the invention, parallel link members areemployed forthis purpose. As shown, link supporting standards 25 and 26are mounted on the top wall l3 at each side thereof adjacent what, forconvenience of description, will be termed the front end of thecarriage. Each of these standards is provided with reduced ends 21 and28, Fig. 3. The reduced end 28 is adapted to extend through the top walland is adapted to be held in position by a nut or other suitablefastening means 29 which is threaded on the end 28 of the standard. Ro-

tatably mounted on the standard 25 is the bearing 3i of a swinging arm32. Suitable anti-friction devices such as the ,ball bearings 33 may beprovided at each end of the bearing 3|, as shown in Fig. 3. This arm maybe of any suitable form, as, for instance, an I-beam as shown,

' which may taper outwardly from its bearing II.

The upper end of the standard 25 may also be 'reduced for extendingthrough an opening in a plate 34 secured against the bearings 33 as by imeans of anut 35.

The standard 28 is mounted in a similar manner, and has joumaled thereonan arm 35 corresponding to the arm 32 described above. The rear ends ofthe arms 32 and 35 are pivotally attached to the bar 23 as at 31 and 33,respectively. These arms extend beneath the bar 23 and are pivotedthereto by journals as the bolts having ball bearings 30 thereon, Fig.4. It will thus be seen that the bar 23 has a parallel movementtransversely to the carriage in such a manner that the bar 23 may bemoved transversely of the carriage. The arms are of the same length andthe distance between the pivots 31 and 33 is the same as between thepivots 35 and 33 so that the \arm 23 may be moved lengthwise and will beheld by the arms 32 and 36 normal to the longitudinal axis of thecarriage at all times. The arms,'having ball bearings, cause the deviceto be easily and readily moved by the operating mechanism, as willpresently appear.

Mounted on one end of the arm 23 is the torch support or torchsupporting device 39 which comprises a clip 4i, Figs. 1 and 4, having adepending threaded stud 42 rigid therewith. The arm 23 is provided witha plurality of openings 43 which are adapted to be engaged by the stud42 for adjusting the support longitudinally of the arm. The clip 4| isprovided with a clamping bolt 44 by means of which the shank 45 of aclamping element 46 may be clamped in position. The shank 45 rotatablyand slidably engages the clip 4| and is held in adjusted position bytightening the bolt 44. The clamping element 48 is adapted to slidablyand rotatably receive the shank 41 of the torch holder 48. A. torch 49is slidablymounted in the holder 48. Preferably, though not necessarily,the torch 43 is provided on one side with a rack 5| which is adapted tobe engaged by a pinion 52 mounted on a shaft 53 having the hand wheel 54at the end thereof (Fig. 4). By rotating the hand wheel 54, the torch49-may be raised and lowered. The clamp is provided with a clamping bolt55 by means of which the shank 41 may be clamped in any adjustedposition.

It will be seen that by means of this arrangement, the torch 49 has auniversal adjustment. It may be adjusted inwardly or outwardly along thearm 23 by applying the shank 42 to any 41 may be adjusted inwardly oroutwardly through the clamp 45 carrying with it the torch 49. The torchmay also be adjusted -forwardly or backwardly by adjusting the shank 45through clamp 45. The torch 49 may also be rotated in a vertical planelongitudinally of the carriage and held in any adjusted position by theclamping bolt 55 which engages the shank 41. The torch may also berotated about a vertical plane transversely of the carriage by firstloosening the clamping bolt 44 which clamps the shank 45.

The torch 49 is'provided with the conventional preheater conduits 56 and51 for the oxygen and acetylene or other combustible gases and theconduit 53 for the high pressure oxygen cutting jet, as is usual in suchconstructions. The low pressure conduits are controlled by a singlevalve 53 which opens and closes the two conduits 55 and 5'!simultaneously and the conduit 53 is provided with a control'Ol. Thecontrols 59 and II are both adjacent to the casing or box 24 so thatthey will be accessible to the operator, as will presently appear. Sincethe construction of the gas conduits constitutes no part of the presentinvention, the same is not described in detail. It will be noted,however, that the controls II and II are accessible to the operatorfrom. his position in operating the machine.

It has been proposed to employ a tracing mechanism or template forguiding the gas cutting torch in its movement during its cuttingoperation. But, more or less difliculty has been experienced inthe useof a tracer element as a tractor mechanism in connection with tracingcharts, prints or papers for the reason that the wheel must be so smallthat the tractor force tends to distort, crumple or disarrange thetracing 'print or chart and consequently, it is more difficult to followthe lines with the tracer.

The present invention seeks to avoid this difficulty by employing atractor wheel separate and apart from the tracer wheel. This arrangementpermits, the use of a comparatively large traction wheel. The tracerwheel must necessarily be small so that sharp angles and turns may befollowed and more accurate tracing may be accomplished. The largetraction wheel will v not disturb the chart or tracing paper or diagramwhile the small tracer wheel will permit extreme- 1y accurate guiding ofthe cutting torch. The

tracing element is geared to the tractor element so that .the. twooperatein synchronism.

On the opposite end of what, for convenience of-description, will betermed the inner end of the arm 23, Fig. 4, are mounted a tracer memberor mechanism 52 and a tractor member or tractor mechanism 63, which willillustrate one embodiment of the invention.

The tracer member 62, Figs. 3 and 11, comprises a shaft 64 extendingthrough a support or casing 65 secured to the arm 23 and has its upperend provided with a hand wheel 65 for turning the tracer. The casing 65comprises a lower section 13 and a removable upper section 81. The shaft64 is. journaled in both sections of the casing 65. The lower end of theshaft 54 is bifurcated and provided with a tracer wheel 67! journaledtherein which is adapted to control the movement of the apparatus. Thetracer shaft 54 is slidably mounted in the's'upport or casing 55 and isyieldably held in lower position by a spring 68, Fig. 11, which engagesthe lower end oi the support casing 65, and a collar 69 adjustablymounted on the shaft 52 by the set screw Suitable means are provided forholding the shaft 64 in inoperative position when th'eapparatus is usedin conjunction with a template, as will presently appear. As shown, acollar H is employed for this purpose. When it is desired to hold theshaft 64 in elevated position, as when a template is used, the set screw12 is released, the shaft 64 elevated, and the collar 1| dropped downinto contact with the upper side of the casing 55 and the set screwtightened while holding the shaft'in elevated position.

Suitable means are also provided for automatically moving the carriagelongitudinally along the rails I9 and 2| and for moving the torchsupporting bar 23 in response to the movement of the tracer 52. Asshown, the tractor mechanism 53 is employed for this purpose. The tracerand tractor mechanisms are mounted adjacent to each a The tractormechanism 53, Figs. 10 and 11, comprises the hollow shaft I4 having itslower end bifurcated as at I5 and provided with aligned I openingswithinwhich a journal 15 is secured. The Journal 15 has'an axial opening30 for receiving the outer end of a radius rod for cutting circles, aswill presently appear. A tractor wheel I1 is-mounted on this journal.The upper end of the shaft I4 is slidably keyed to a sleeve I8, Fig. 10,which, in turn, is joumaled in a two-part bearing I9, one part of whichis integral with the lowerportion of the casing 65 and the other part H9is held by the bolts III, as shown in Figs. 11 and 3. Theupper end ofthe sleeve I8 is also provided with flanges 99 resting on shouledrs I9within the casing 65 and the lower end of this tween an internal annularledge 82 on the upper end of the sleeve I9 and the upper end of theshaft I4 normally forces the shaft downwardly and with it the tractorwheel '11 for lowering the tractor mechanism, as will presently appear.

Means are provided for operating the traction wheel 17 while theapparatus is in use. .As shown, a motor 93 mounted within the box 24,Figs. 6 and 7, is employed for this purpose. The .power from the motor83 is taken through a change speed gear mechanism 84 for operating thepower shaft 85, Fig. 6. The power shaft 85, extending into the sectionI3 of the casing 55, Fig. 10, is provided with a bevel pinion 88 on itsouter end which -is adapted to engage a bevel gear 99 slidably keyed toa countershaft 9| which extends downwardly through the hollow shaft I4and has a collar 92 mounted on its lower end for limiting the downwardmovement of said hollow shaft. The upper end of the shaft 9| has its'upper end journaled in a sleeve 93, as shown' more clearly in Fig. 10.The upper section 81 of the casing 65 has mounted thereon a flangedsleeve 94 through which the shaft 9| extends. The tractor mechanism maybe elevated when the tractor wheel is not to be used. As shown,- theupper end of the sleeve 94 is Provided with cam surfaces 95, Fig. 11,which are adapted to be engaged by pins 96 and 91 rigidly connected toopposite sides of the sleeve 93. The sleeve 93 is provided with a handlemember 98 whereby upon rotating the handle 99 and with it the sleeve 93,the pins will ride up the cam and elevate the shaft 9| against thecompression of the spring 8I-. The shaft 9| is supported by the sleeve93 by the head 99 of a screw threaded into the upper I end of the shaft9|, as shown more clearly in Fig. 10. The head 99 rests on the'innerrace of anti-friction bearings I9I, the outer race of which 7 in turnrests on the annular shoulder or flange I92 on the sleeve 93. Keyed tothe shaft 9| is the bevel gear 89 which is journaled in a split bearingI93 rigid with the lower section I3 of the casing 95. The keyway I94 forthe shaft 9| extends to the upper end of said shaft so that by removingthe cap screw 99, the shaft 9| and with it the sleeve I4 may be removedfrom the casing 91. The lower end of the shaft 9| is provided with aworm I95 which is adapted to engage a worm gear I96 onthe shaft I01.Keyed to the shaft I9! is a spur gear I98 which meshes with a spur gearI99 rigidly mounted on the hub II9 rotation of the shaft 9| will causethe rotation of the countershaft I91 through the worm I95 and gear I96and this in turn will rotate the traction wheel 11 through the gears I98and- I 99. The gear I99 is rigid with the hub N9 of the tractor wheel11.

Suitable means are provided for guiding the movement of the tractorwheel 11 in response to the angular movement of the tracer member 62. Asshown, the tracer member 62 has slidably keyed thereto a gear II9 whichis adapted to be engaged by an idler gear III which in turn meshes witha gear II8 non-rotatably mounted on the upper reduced end- 9 of thesleeve III, as shown in Figs. 10 and 11.

When the operator turns the wheel 96, the sleeve 19 is rotated throughthe chain of gears H6, H1 and .II8 and since the hollow shaft I4 isslidably keyed to the sleeve I8, the shaft I4 and with it the tractorwheel I! will be turned through the same angle due to the fact that thegears IIS and 8 are the same size or rather have the same number ofteeth.

In cutting metal sheets of different thicknesses and different material,it is necessary that the speed of the traction wheel ll be varied. Avariable speed motor and a suitable change speed mechanism I 2| isemployed for this purpose. The change speed mechanism varies the gearratio between the driving and driven shafts and the use of a variablespeed motor permits flne adjustments of speed between the change speedadjustments. For the purpose of disclosure, mechanism for obtaining fourdifferent change speeds will be described. The first speed will beconsidered the lowest in the following description.

This change speed mechanism I2I is mounted in the box 24 and comprises apinion I22 which is mounted on the motor or power shaft I23, Figs. 7 and9. This pinion I22 is in permanent engagement with a gear I24. The gearI24 is mounted on a shaft I25 on which a pinion I29 is keyed. The pinionI29 is in permanent mesh with a gear I2'I fast on the shaft I28 andkeyed to this shaft I 28 is a pinion I29 in mesh with a gear I3I whichis turn is keyed to a shaft I32 on which is keyed a pinion I33 which inturn is in permanent mesh with the gear I34. Slidably keyed on the powershaft 85 is a master gear I which is adapted to be shifted into meshwith the gear I24 for the fourth or highest speed; into mesh with thegear I21 for the third speed; with the gear I3I for obtaining secondspeed; or. with the gear I34 for obtaining first or the low.- est speed.The gear I35 is shifted by means of a yoke I36 (Fig. 6), carried by orrigidly connected to a slidable rack I31. An idler gear I38 (Fig. 8) isin permanent mesh with the rack I31 and is also in permanent mesh withthe pinion I39 on the shaft MI.

The shaft I4I extends through the top wall of the motor casing 24, andhas an arm I42 attached thereto (Fig. 7). The arm swings over anindicator plate I43, having openings I44 therein and with legendsthereon for indicating the different speeds. A spring-pressed detent I45carried by the outer-ends of the arm I42 is adapted to engage in theopenings I44 for holding the change speed mechanism in adjustedposition. Openings I59 are provided in the indicator plate I43 at pointsmidway between the openings I44, so that when'the detent I45 engagesthese openings the master gear I35 will not be in mesh with any of thechange speed gears. In other words, these positions may be termedneutral. When the arm I42 is in the position shown in Figs. 1, 6 and '7,the gear I35 has been moved into mesh with the gear I34 to provide thefirst or lowest speed. By moving the arm to the left in Fig. l, the gearI35 will be brought into mesh with the gear I3 I, and the second or.nextto the lowest speed will be obtained. The gear I35 may be moved intomesh with the gear I21 for third speed, or moved still furtherintomeshwith the gear I24 for obtaining fourth or highest speed.

The motor is of the reversible variable speed type, and the apparatus isprovided with a rheo-v stat I46 whereby variations of speed may be hadbetween the different speeds obtained by the gearsof the change speedmechanism. The rheochange speed is reversed, or for reversing the motorat other times when it is desired. As shown, a switch I41 is providedfor this purpose. The switch I41, when moved to one side, will causethemotor shaft to turn in one direction, and when moved to the oppositeextreme will cause the motor shaft to move in the opposite direction.

' Suitable means are provided-on the inner end of the bar 23 foroperating the switch. I41, as

shown in Fig. 4. As shown, a lever I48 is pivoted at its lower end andhas attached to its in termediate portion a rod I49 which is attached tothe switch I41 at its outer end, as shown in said figure. The switchlever I48 islocated at the inner end of the bar 23 so that all thecontrols will be accessible to the operator when he is operating thewheel 66 for guiding the tracer wheel 62.

.In the form of the construction described above, a tracing sheet orpaper II is secured in position beneath the tracer and tractor members.as shown in Fig. 1, after the same have first been elevated and theoperator, after placing the material to be cut beneath the torch andsetting the machine to proper speed, lowers the tracer member 62 and thetractor member onto the sheet and then turns the switch I 41 whichcauses the tractor member to move along the tracing I5I. The operator,by means of the handle 66,

' guides the tracer wheel along the lines I52 of the drawing, pattern ortracing sheet I5I, Fig. 1, thus causing the torch to cut the metalaccording to the pattern or outline traced by the tracer member 62.

In the form of the tracing shown in Fig. 1, the tracer member can becaused to follow the pattern I52 without reversing the motor. But, whenthe pattern is like that shown at I53 on the pattern sheet I54, Fig. 2;that is, a pattern in which there are sharp angles as at I55, the motormay be reversed when the tracer wheel 62 reaches the apex of the angle,as shown in full lines, so that it"may be readily rotated to the dottedline position shown at I56 which necessitates moving the tracer wheel 52only through a small angle whereas without reversing the motor, thetractor wheel would form a curve because it could not be made to formthe sharp angle unless the same be first elevated from the pattern orsketch, since the tractor wheel 11 would continue to travelalong thetracing while it. is being turned. This is considered an importantfeature or the invention because it insures sharpness in the angle andalso greatly simplifies the operation.

A suitable attachment is provided for use on the apparatus when it isdesired to cut the metal to form disks, circles or segments of circles.In

the construction selected to illustrate one form of the invention, aplate I51 has attached to its central portion a swivel standard I58having a clamping member I59 on its upper end. A radius rod I6I isslidable through the clamp I59 and is held in adjusted position by anysuitable means such as the set screw I62. The standard I58 is rotatablymounted in a base I63 rig y secured to the plate I51. The outer end ofthe rod I6I'is provided with a collar I84 spaced from theend and thethreaded end is provided with a nut I65 for clamping a support betweenth collar and the nut. I

'When it is desired to cut the metal to circular form, the nut I65 isremoved and the rod inserted through the axial opening 99 inthe bearing16, Fig. 11, and the nut I65 applied for clamping th rod in position,The tracer member 51 is then elevated out of contact with the plate I51and the rod is clamped in position so that it will have the desiredradius. It will thus be seen that when the rod is applied as shown inFig. 15, that the tractor wheel 11 will describe a circle about the postI58. The length of the radius of this circle may be adjusted by slidingand adjusting the rod.

In Fig. 13 is shown a modified form of tractor member for the apparatus.In this form of construction, a template IE6 is provided for guiding thetractor mechanism. As shown, a modified form of tractor mechanism issubstituted for the tractor mechanism 63 shown in Fig. 11. In this formof construction, two tractor members I51 and IE8 are employed, the lowerends of which are tapered and knurled as at I69and I1I. The track ortemplate I66, which guides the cutting torch, is received between theinc ined surfaces I59 and HI as shown at the lower portion of Fig. 13.

Suitable difierential mechanism is employed for compensating for theunequal rotations of the two tractor members in moving around curves onthe template. As shown, tractor members I61 and I68 have upwardlyextending shafts I12 and I13 which extend through the lower end of thehollow head I14 and have gears I15 and I16 on the upper ends thereof.These ars are in mesh with the spur gears I11 and I18 mounted ontheshafts I19 and I8I which are joumaled in the inwardly extendingprojections I82 and I83 on the head I14. The shafts I19 and I8 I areprovided at their upper ends with bevel gears I84 and I85 which are inmesh with corresponding bevel gears I86 and I81 on a pair of stub orcounter shafts I88 and I89, respectively. Connecting the inner ends ofthe shafts I88 and I89 is a diiferential mechanism I9I. Since thedifferential mechanism is of the usual or any well known construction,it is not thought necessary to describe the same in detail.

Carried by the cage I92 of the diii'erential mechanism is the ring gearI93 which is adapted to engage a bevel pinion I94 on the lower end ofthe shaft I95 which corresponds to the shaft 9| in the previousconstruction.

The head I14 is provided with a closure I96 which is rigidly held inposition on the head as ings.

which is screw threaded at its upper end for ref ceiving a nut 200. Thereduced portion I99 is Journaled in a sleeve 2M which in turn is keyedto the sleeve I8 as shown in Fig. 13 of the draw- In substituting thehead ill for the tractor member 63 it is only necessary to remove theset screw 99 and then remove the entire tractor mechanism 93 downwardlythrough the sleeve 18. The head I" and shaft I95, together with thesleeve 20! is inserted in the sleeve 18 ,and the set screw 99 replaced.I

In Figs. 17 and 18 is shown a modified form of means for holding orattaching a plurality of torches to the torch supporting bar 23a. Inthis form of construction, the outer end of the torch supporting bar 23ais provided with a sleeve or slide 203 through which a rack)! is adaptedto slide longitudinally of the bar 23a for adjusting the torch to andfrom the bar 23a. A pinion 205 having a stem and hand wheel 206extending upwardly therethrough is provided in the sleeve or clamp 203with the pinion in mesh with the rack so as to adjust the racklongitudinally of the bar 23a when the hand wheel 206 is rotated. Theouter end or the rack 204 is provided with an integral clamping sleeve20! through which a rod 208 is adapted to be slid or rotatedtransversely to the rack. The clamp 20'! is provided with a suitablemeans such as the clamping screw 209 for holding the rod 208 in adjustedposition.

Each end of these arms may be provided with a torch supporting andadjusting mechanism 2 l0. Since the two structures 2) are duplicates,only one need be described.

Slidably mounted on the end of the rod 208 is a clamping member 2 havinga clamping screw 2l2 for holding the clamp in angular or longitudinaladjustment on the rod 208. The clamp 2 has provided in its lower surfacea clamping member 2 I 3 through which a torch supporting rod 2 isadapted to slide or rotate. The rod maybe held in adjusted position byany suit able means such as the clamping screw 215, as shown moreclearly in Fig. 18 of the drawings. The outer end of the rod 2 isprovided with a clamping member 6 for holding the torch 2H. The torch isprovided with a vertically extending rack 218 and the clamp M8 isprovided with a pinion 219 which corresponds to the pinion 52 of theprevious construction. The pinion is mounted on a shaft having a handwheel 22! by means of which the pinion may be rotated for raising andlowering the torch 2" through the clamp 2l6.

The clamping member 203 may be adiustably secured to the arm 23a in anysuitable manner. As shown, the clamp is provided with a downwardlyextending shank 222, Fig. 18, which is screw threaded at its lower endfor receiving a clamping nut 223 by means of which the clamp is rigidlysecured in position in any one of a series of openings 43a on the arm23a. By means of the'shank 222, the arm 298 may beangularly adjustedrelative to the bar 23a it it is so desired.

It will thus be seen that by the use or the torchholding mechanismdescribed the torch may be raised and lowered by rotating the hand wheel22!; it may be moved outwardly and inwardly by rotating the hand wheel206: it may be moved around the bar 208 by loosening the clamp 2; or itmay be rotated in a plane transverse to the bar 23a by loosening theclamp Ill. The other scope or the appended claims.

torch may likewise be angularly adjusted in planes parallel with, andtransverselyt the bar 23a, and alsoraised, lowered and moved outward toand from the supporting rod 208 and to and from the bar.23a. Additionaltorches may be mounted on the rod 208, or all may be removed except one,as conditions may require.

In Fig. 14 is shown a modified form of tractor wheel for the tracermember. In this form of construction the wheel Ila is provided with aperipheral groove within which is mounted av rubber tire I'Ib. Otherwisethe construction of this wheel is the same as the wheel 11, for which itmay be substituted.

It is thought from the foregoing, taken in connection with theaccompanying drawings, that the construction and operation of my devicewill be apparent to those skilled in the art, and that changes in size,shape, proportion and detail may be made without departing from thespirit I claim as my invention:

1. In a gascutting apparatus, a carriage, a torch supporting barextending across said carriage to opposite sides thereof, a torchsupporting head, means for mounting said head on one end of said bar foruniversal adjustment of said head, a tracer wheel member on the oppositeend of said bar for guiding the movements of said bar and carriage, atractor, a motor and change speed mechanism mounted on the centralportion of said bar and movable therewith, and means for operating saidtractor from said motor and change speed mechanism.

2; In a gas cutting apparatus, a carriage, movable parallel armmechanism carried by said carriage, a torch mounted on said mechanism,tracer wheel means carried on said mechanism, means for manually guidingsaid tracer, a tractor associated with said tracer, a reversible motoron said mechanism spaced from said tracer for operating said tractor,and change speed mechanism for operating said tractor from said motorwhereby said tractor may be operated at diiferent speeds both forwardlyand backwardly. I

3. In a gas cutting apparatus, a carriage, a track for said carriage,'agas torch supporting bar, parallel link mechanism for supporting saidbar from said carriage, a gas cutting torch carried by said bar, asingle tractor member carried by said bar for moving said bar and torch,a tracer wheel member for engaging a pattern sheet and for tracing linesthereon, and means interconnecting the tracer and tractor members forpositively directing the movements of said tractor member irom saidtracer wheel member.

4. In a gas cutting apparatus, a carriage, a track for said carriage, agas torch supporting bar, parallel link mechanism for supporting saidbar from said carriage, a gas cutting torch carried by said bar, tractormeans carried by said bar for moving said bar and torch, a tracer wheelmember onset from the tractor means for engaging a pattern sheet fortracing lines thereon, and means interconnecting the tracer member andtractor means for positively directing the movements or said tractormeans from said tracer wheel member.

5. In a gas cutting apparatus, a carriage, a track on which saidcarriage may travel, a torch supporting bar, a pair of links of equallengths and - said tracer member.

6. In a gas cutting apparatus, a carriage, a torch supporting bar, meansfor movably supporting said bar from said carriage, a torch carried bysaid bar, a tractor member carried bysaid bar, means onsaid bar 'foroperating said tractor member for moving said bar and carriage, atracermember having an upwardly extending standard swivelled in said torchsupporting bar, a hand wheel on the upper end of said standard forrotating the same, means for swivelly mounting said tractor member onsaid bar, and gear mechanism for causing said tractor member to rotatesynchronously with the rotation with said hand wheel.

'l. Ina gas cutting apparatus, a carriage, a torch supporting bar, meansfor movably supporting said'bar from said carriage, a torch carried bysaid bar, a tractor member carried by said bar, means on said-bar foroperating said tractor member for moving said bar and carriage, a tracermember oflset from said tractor member and adapted to engage a tracing,means for steering said tracer member, means including an operativeconnection between said tracer and tractor members for controlling thedirection of movement of saidtractor member upon steering said tracermember, said last-named means comprising a motor, and change speedmechanism for operating said tractor member from said motor at differentspeeds.

8. In a gas cutting apparatus, a carriage, a torch supporting bar, meansfor movably supporting said bar from said carriage, a torch car ried bysaid bar, a tractor member carried by said bar, means on said bar foroperating said tractor member for moving said bar and carriage, a tracerwheel ofiset from said tractor member for engaging a tracing sheet,interconnecting gears between said tractor and tracer members, means formanually turning said tracer wheel member about a vertical axis forchanging the direction of movement of said tractor member throughvarious angles, a reversible motor, and change speed mechanism foroperating said tractor member from said motor at different speeds, saidchange speed mechanism reversing the direction of rotation of saidtractor member on changing from one speed to the next adjacent speedwhereby the direction of rotation of said tractor member on changingspeed may be made to continue in the same direction by reversing saidmotor.

9. In a gas cutting apparatus, a carriage, a torch supportingbar'movably mounted on said carriage, a tractor member mounted on saidbar, a reversible motor carried by said bar, a vertical shaft rotatablymounted, on said bar, a tracer wheel ofiset from said tractor memberrotatably mounted on said shaft, intermeshing gear mechanism for turningsaid tractor member about a vertical axis from said tracer member, ahandle member on said shaft for manuallytuming the same for tracing theoutlineof a pattern for causing said torch to reproduce such outline assaid tractor member moves said bar, a change speed mechanism for saidtractor member, said change speed mechanism comprising a train of speedreducing gears and pinions permanently intermeshing, and a shiftablegear shiftable into mesh in a continuous order with said gear forobtaining difierent speeds for said tractor member, said motor being ofthe variable speed reversible type whereby very fine adjustments of thespeed of said tractor member may be obtained while moving eitherforwardly or 'rearwardly.

10. In a gas cutting apparatus, a carriage, a torch supporting bar,means for movably supporting said bar from said carriage, a torchcarried by said bar, a single tractor wheel member carried by said bar,means on said bar for operating said tractor member for moving said barand carriage, a tracer wheel member, means for controlling the directionof movement of said tracer wheel member, said tracer wheel member beingoflset Irom said tractor wheel member, means including a train of gearsinterposed between said tracer and tractor wheel members for steeringsaid tractor wheel member upon steer-, ing said tracer wheel member, areversible mo-; tor, and change speed mechanism for operating;

said tractor member from said motor at different-,1

handles being easily accessibleto the operator; while in position foroperating said tracer member.

11. In a gas cutting apparatus, a carriage, a substantially straighttrack for said carriage, a pair of standards on said carriage, parallelswinging arms journaled on said standards, a torch supporting barextending transversely to said carriage and pivotally attached to saidbar, a tractor member swivelly mounted on one end of said bar, a torchadjustably mounted on the opposite end of said bar, conduits forconducting preheating and cutting gases to said torch, valves for saidconduits, controls for said valves, a tracer wheel member adjacent tosaid tractor member and in advance thereof when moving straight aheadunder normal operating conditions, means including a handle member onsaid tracer member for simultaneously controlling the direction ofmovement of said tracer and tractor members, a reversible variable speedmotor carried by said bar, means for operating said tractor member fromsaid motor, a control for reversing said motor, and a control forvarying the speed for adjusting said clamp along said bar and forrigidly securing the same in'position, a second clamp having aroundshank rotatable and lengthwise adjustable in said first namedclamp,

a torch holder sleeve having a shank Irotatably and slidably adjusted insaid second clamp, a torch slidably mounted in said sleeve, and meansfor raising and lowering said torch.

13. In a gas cutting apparatus, a carriage, a gas cutting torch, means,including a bar, for movably mounting said tor on said carriage,

' said means comprising a sleeve mounted on said -bar'1and rotatableabout a vertical axis, means for adjusting said sleeve along said barand for rigidly securing the same in position, a rack slidable throughsaid sleeve, means including a pinion engaging said rack for adjustablymoving said rack through said sleeve, a clamp on the outer end of saidrack, a rod slidably and rotatably mounted in said sleeve, 9. pair oftorches,

and means for adjustably mounting said torches on the end portions orsaid rod in such manner that said torch may be raised andlowered andmoved in planes parallel with said bar or at an angle thereto.

r 14. In a gas cutting apparatus, a. carriage, movable parallel armmechanism carried by said carriages. torch mounted on said mechanism, atractor wheel at one end of said mechanism, wheel tracer means carriedon said mechanism 'for guiding said tractor wheel, and a motor mountedon an intermediate portion at said arm mechanism and spaced a materialdistance from w said tractor for operating said tractor.

FRED STONEBERG.

